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Design >> Analog Design >> resistor TC
https://designers-guide.org/forum/YaBB.pl?num=1150617740

Message started by microe on Jun 18^th, 2006, 1:02am

Title: resistor TC
Post by microe on Jun 18^th, 2006, 1:02am

I see in some process documents that N+ poly resistor has a negative Temperature coefficient while P+ poly resistor has a positive TC. What is the physical reason of that? Is it possible to have N+ poly with positive TC or P+ poly with negative TC?

Thanks.

Title: Re: resistor TC
Post by jhuang on Jul 28^th, 2006, 1:45pm

From the device physics, the resistance is inversely proportional to both mobility and carrier concentration. The mobility has a negative TC while the carrier concentration has a positive TC. So it all depends on which is dominant or more specifically the sheet resistance. I actually used such a process with NTC from p-poly and PTC from n-poly.